Paper-supported polystyrene membranes for micro-solid phase extraction of date-rape drugs from urine: A sustainable...

The rapid development of micro-solid phase extraction (μ-SPE) procedures with new sorption materials, in particular, based on using natural materials, is currently reported. The production of these sorbents and the entire extraction procedure should support the implementation of Green Analytical Chemistry (GAC) principles. Promising materials are sorbents based on paper, which can be relatively easily modified, among others: by covering it with a polymer membrane. In this work, the practical application of paper-supported polystyrene used in the analysis of urine samples containing selected date-rape drugs (DRD) substances, and evaluation of the entire procedure using GAC metrics is presented.

The paper-supported polystyrene membranes were successfully fabricated and characterized. The successful polystyrene coating on the paper was confirmed through ATR-FTIR measurements, ensuring even coverage. The μ-SPE procedure using this material facilitated extraction with a throughput of approximately 120 samples per hour in just a few steps. Throughout the research, a mixture of 100 mM acetic acid:methanol:acetonitrile (70:15:15, v/v/v) was selected as an optimal background electrolyte for capillary electrophoresis - mass spectrometry analysis. Validation results of this method demonstrated its suitability, exhibiting good linearity (R² > 0.95), low limits of detection (3.1-15 ng mL^-1), acceptable precision (<15 %), and recovery for all tested analytes. Furthermore, the greenness evaluation conducted with six different metrics: AGREEprep, AGREE, ComplexGAPI, SPMS, hexagonal metric, and WAC indicated the overall eco-friendliness and sustainability of the method, with minor concerns regarding energy consumption.

The use of cellulose paper with polystyrene membranes for μ-SPE provides a versatile and eco-friendly extraction method for detecting DRDs in urine samples. The presented work is an example of the use of GAC metrics in the evaluation of the analytical procedure. The optimized PT-μ-SPE/CE-MS method allows for minimized reagent usage and waste production. Moreover, the method proves to be sustainable and efficient for forensic toxicology analysis.